How to create a slinky animation in blender?
You can generate the mesh of your slinky using the screw modifier on a crossection mesh. Then you want to use a Bézier to deform your slinky.  You can animate the whole thing by applying shape keys to your curve. You can simply key frame these.

You will encounter a problem regarding how far your object stretches along the curve. I have no solution but key framing the z scale yet. But I think you can calculate the length of your Bézier and write a driver for it if it is too much to animate. Which is way more difficult for a beginner.

a lattice might improve the destribution of your slinky along the curve.